Apparatus for administering anesthetics or analgesics.



M. F. EWEN. APPARATUS FOR ADMlNISTERINGANESTHETICS 0R ANALGESICS.

APPLICATION FILED APR.Z9,1916.

Patentecl Feb. 12, 1918.

3 SHEETS-SHEET l.

M. F. EWEN. APPARATUS FOR ADMINlSTERlNG ANESTHETICS 0R ANALGESlCS. APPLICATION FILED APR. 29. me.

11. fifi gl Patented Feb. 12, 1918.

3 SHEETS-SHEET 2 Ill! 7/ 39 10 rum/1111 g0 lza MALCOLM F. EWEN, OF CHICAGO, ILLINOIS, ASSIGNOR TO CENTRAL TRUST COMPANY OF ILLINOIS, TRUSTEE, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

APPARATUS FOR. ADMINISTERING ANES'IHE'IICS OR ANALGESICS Specification of Letters Patent.

Patented Feb. 12, 1918.

Application filed April 29, 1916. Serial No. 94,316.

To all whom it may concern:

Be it known that I, MALCOLM F. Ewen, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Apparatus for Administering Anesthetics or Analgesics; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to an apparatus for administering anesthetics or analgesics and consists of the matters hereinafter described and more particularly pointed out in the appended claims.

The invention relates more particularly to improvements in the form of apparatus shown and described in an application for Letters Patent heretofore filed April 3rd, 1915, by Will P. W alter, Serial Number 18,868, relating to an apparatus for administering anesthetics and is primarily intended for use in connection with such operations where chloroform, ether or the like is not required and only gases or vapors forming an analgesic mixture are necessary.

The object of the invention is to simplify the form of the apparatus; to provide an improved and more easily readable form of sight feed gage device to determine the proportions of the gases in the analgesic or anesthetic mixture; to provide an improved device whereby the said proportions may be preliminarily determined and whereby the flow of gases forming the mixture may thereafter be controlled by a member operable by one hand; to provide means for preventing an excess of pressure above a certain low pressure from being brought to bear upon the lungs of the patient; and to provide improved connections whereby the.

gas cylinders of dilferent lengths are made capable of attachment to the apparatus.

These and various other objects and advantages of my invention will. appear more clearly as I proceed with my specification.

Referring now to the drawings Figure 1 is a view representing my improved apparatus in front elevation with the gas or vapor cylinders connected thereto. Fig. 2 is a view representing the same in side elevation. I

Fig. 3 is a view representing a, vertical section of the apparatus in a plane indicated by the line 3-3 of Fig. 2.

F ig. at is a top plan view of the apparatus with the cap or cover removed.

Fig. 5 is a view representing a partial vertical section through one of the sight feed tubes of the pparatus.

Fig. 6 is a view representing a vertical section through the other sight tube of the apparatus.

Fig. 7 is a view representing a vertical section through the apparatus in a plane indicated by the line 77 of Fig. 1.

Fig. 8 is a view representing a transverse section through the apparatus in a plane indicated by the line 8-8 of Fig. 7.

Referring now to that embodiment of my invention illustrated in the drawings :10 indicates a casing, preferably made of metal, which provides a support for a head 11, that contains the valve mechanism of the improved device, and that also has attached to it the yokes 12, by means of which the gas or vapor cylinders which supply the constituents for the analgesic or anesthetic mixture, are connected to the device. The said casing also provides a protecting closure for a transparent vessel or jar 13 in which are located upright transparent sight feed gage tubes 14, let. This jar contains the water or other washing fluid by means of which the gases or vapors forming the anesthetic mixture are washed before being administered to the patient.

As shown, the casing 10 is a tubular, substantially rectangular shell which is open at the top and which has a bottom wall 15. It is preferably provided with an open base 16 having a plurality of spaced foot pieces 17 made of elastic material such as rubber or the like, to prevent the metal of the casing from marring Or scratching a table or desk upon which the apparatus is placed.

The transparent vessel 13 consists of a glass tube which as shown is of cylindric form and is of such diameter as to fit easily within the casing 10. Said tube is closed at the top and bottom respectively by means of elastic disks or gaskets 18, 19, made of rubber or other like material. The head 11 is a plate which closes on the elastic disk covering the top of the glass tube 13 and which is attached to inwardly projecting ears 22 formed at the top of the casing 10, by means of screws 23. By means of said screws, manifestly the head may be drawn means oi a hand-controlled shut-oil or pet down upon the casing 10, so as to tightly seal the ends of the transparent tube 13 against the elastic disks 18 and 19 at the bottom and top respectively of said tube.

The sight feed gage tubes let, 14; are each preferably made in two parts, a bottom part 14B of glass or other suitable transparent material, and a top part 1 1 of metal. An

annular elastic washer 14c is interposed between the two parts and each tube as a whole issealed at top and bottom by means of annularbosses, 24, 25., formed respectively upon the top and bottom disks or, gaskets 18,19, The ends of said tubes are depressed into the elastic material forming the said gaskets and the abutting ends of the two parts of each tube are tightly engaged against the interposed washer when tle head 11 is drawn down upon the casing. so

that-the s ght feed gage tubes like the,

larger outer tube 13, are securely sealed against leak-age A recess 26 is formed in the bottom wall 1 5 of the casing 10 con necting points below the two sight feed gage tubes and the said sight feed gage tubes-are connected with the interior or" the larger tube 13 by means of passages 27, 27, opening from the sight feed gage tubes into the recess26, and a passage 28 connecting said recess w'th the interior of the larger tube 13.

There. is providedon the head 11- an upright boss 29, in which are formed two valve casings 30, 30-, one associated with each sight feed gage tube. Each valve casing opens by means of a passageway 31 extending through the top gasket 18 into its; associated sight'ct'eed gage tube. Each valve casing contains, a needle valve 32 that controls the flow through said passage 31 from a passage 33 that is connectedrby cock valve 3 1 to the usual nipple 35 of the yoke 12 which is adapted to be connected to the neck of the gas or vapor cylinder in a familiar manner. 7

Pressure reducing valves 36 are interposed between the nipples 35 and the valves 3t, said reducing valves being connected by brackets 37, 38, respectively, to the yokes. 12 and to the head 11. The valve plug, of; each pet-cock valve 34 is adapted to be rotated by. means of a radial arm 39, and the arms of the two valves are connected by links 10 which is made of such lateral dimensions that the necks 14 of the gas cylinders-45 may be engaged therein and still rest withtheir bottom ends on the support upon which the casing 10 rests; that is to say, these yokes are so constructed as shown, that the cylinders may be inclined at difierent angles, as illustrated in Fig. 2, of the drawings, without interfering with the proper engagement of their necks within theyokes. The outer end members 12 of the yokes 12 have threaded through them the famil ar clamp- 7 'ing screws 12 located in axial ahnement with the nipples 35 and adapted to-securely clamp the neck of the gas cylinders in gas tight engagement with the nipples.

From the construction thus far described, it will be apparent that the pressure of the gas escaping from the cylindersmay be reduced by means of the reducing valves 36, so that the apparatus will not be subjected at any time to any great pressure. Thus, whether the gas cylinders are full or. only partially filled, the pressure induced in the apparatus will'always be low- I The valves 34 are mere shut-off valves, but the valves controlled by the needles 32 are adjustable to determine the flow of gas from said shut-off valvesto the sight tubes 14, 145*. Thus, manifestly, by adjusting the opening of the valves 32 relative, the one to the other, a proportionate rate of flow of the gases'from the two shut-olfvalves may be carefully. predetermined.

The jar l3is filled; in av manner presently to be described with the washing liquid up to a certain. level, for example, that shown inthe' drawings. When no gas is flowing intothe sight 'feed gage tubes 11, 14:, the

7 liquid willstandi at the same level. in the jar and in thetubes, since said tubesare connected to the jar by. the passageway provided by the recess '26 in. the bottom wall ofthe casing 10. ,7 When gas is admitted into the sight feed gage tubes 14, the pressure of the gas will act to depress the level of the water in the tubes, below the-level. in the vessel 13,

partof the liquid in said tubes beingfforced V out through the passage 27, the recess 26 and the passage 28 into the jar 13; It will be manifest that the relative amount of decape of gas to the vessel 13. Said openings are located below the normal level; of the washing liquid in the said vessel 13;, said openings are made. in themetal part of each tube and; 1t. 1s on account of the difiiculty of making these openings, or apertures in glass. that the tubes arevmade in two parts (metal and glass) as described. Preferably single opening, 14:", in the tube 14:, is countersunk or flared as shown in Fig. 5, to prevent capillary attraction from obstructing the free escape of the gas or vapor from the tube. This construction is not necessary in the openings of the other tube, in, from which thefiow of gas is greater in volume and wherein the openings have straight sides, as indicated in Fig. 6.

The gas entering into the tubes 14, 14', escapes below the level of and into the body of the liquid contained in the jar 13, and thence bubbles up into the space above the level of said liquid. From there it escapes through a passage 46, provided in the boss 29 of the head 11, which passage extends upwardly and then continues forwardly and outwardly through a nipple 4-7 formed at the front of the head (see Fig. 7). Said nipple is adapted to be connected with the tube leading to the face or mouth appliance or other device by means'of which the gas mixture is to be administered to the patient in a familiar manner. As the friction to which the gases are subjected in their passage through the apparatus to the nipple 17 is substantially the same in the case of both gases, the'amount of gas in the mixture will be substantially proportional to the relative pressures induced in the said sight feed gage tubes and in proportion to the cross sectional area of the orifices 14, 14, through which they escape from the said tubes. Thus, with the relative cross sectional areas of the openings 14 1-1, fixed (in the apparatus as illustrated in the relation of 1 to 3) the levels of the liquid in the said tubes may be used as a gage to determine the proportions of the gases in the anesthetic mixture. For example, in the apparatus illustrated, if the liquid in the two tubes is depressed (by the adjustment of the needle valves 32) to the same level the proportion of the gases in the mixture will be 1 to 3. If the valves were adjusted so that the liquid in the tube 14- is depressed one-half as much below the level. of the liquid in the vessel 13 as it is depressed in the tube 141, the proportions of the gases in the mixture will be as 1 to 6.

In addition the amount of depression of the liquid in the sight feed gage tubes below the level of the vessel 13 will determine the head and the rate of flow; that is to say, a greater depression of the liquid in the sight teed gage tubes will determine a greater flow of the mixture, while a lesser depression in the sight feed gage tubes will determine a lesser flow. Thus, manifestly, these tubes provide means for visually or optically determining not only the proportion of gases in the mixture but also a greater or less flow of the mixture.

I provide a card 18 which as shown, is graduated and which may be provided with any suitable indicia in order to indicate the relative proportions of the gas pressures in the mixture when the liquid is depressed in the tubes to certain indicatedlevels.

lVith this card may be used a separate index which may be carefully worked out and which will indicate that in order to get a certain desired proportion of each gas in the anesthetic mixture, the level in one tube will have to be depressed to one point on the gage, whereas the other will have to be depressed to another point on the gage.

The casing 10 has a wide vertically elongated opening 10 in its front wall (see Fig. 1), to disclose thesight feed tubes 14. 1-1 and the associated card 18 to view. it clesired the liquid and card may be given contrasting colors so as to make the reading of the scale on the card and the levels in the tubes l-l, 1 1 more quickly and. easily determinable.

In using the apparatus, the hand vaives or pet-cocks 34 are both opened wide and the needle valves 32 are each adjusted until the level of the liquid in the associated tube 1% is brought to the required number or index mark on the card to produce the mixture having the two gases in the desired proportion. The hand-valves 34: are then closed and the apparatus is ready for use. The mask is then applied to the patient in the usual fashion and all that is necessary to do is to open the hand valves by means of the common operating member 13 and the mixture will then be delivered from the apparatus with the two gases in the proportions which were determined by the adjustment of the needle valves in the first instance.

An upright screw or pin 57 (see Figs. and 7) is fixed to the head 11 in position to strike the lever 41 and limit the movement of said lever and consequently of the operating member 43, in closing the shut-0ft valves. This prevents the operating parts from being thrown upon a dead center. The head 11 is inclosed by a tubular eap 1], which has suitable apertures through which the needle valve stems 32 and the operating shaft or pin 42 project. Thus the several valves may be operated as described without removing said cap. The side walls oi said cap also have suitable apertures for the parts of the apparatus which extend laterally beyond the head.

The washing liquid is admitted into the glass vessel through a tube 49 fixed in the head 11 and depending through an aperture in the head into said vessel.

The tube 49 depends into a comparatively larger tube- 51 which is arranged upright.

within the jar 13 and is fixed to and rises from the base 15 of the casing 10. The said tube 51 rises nearly to the top of thejar and has a closed bottom wall The construction described forms a seal. When the washing fluid is poured into the tube 49 it will fill the tube 51 and, rising in the tube, overflow into the glass jar. This may be continued until the liquid is raised to the desired level in the glass jar. Theair or other gas within the jar escapes through the pasend, which has somewhat larger diameter and is adapted to be slipped upon the top of the tube 19. The tube a9 has a constricted opening 49 at its bottom end of somewhat smaller diameter than the internal diameter of the tube itself, and an upright tube 49* is fixed in said 0 enino' said tube rising to a point shortly below the top of the large tube 51. This construction provides a blow-off which is adapted to preventthe anesthetlc gas from being administered to the patient 7 at pessure higher than a determined amount, namely, the pressure required to overcome the head represented by the differ ence in level of the washing liquid in the tube 51 and the level of said liquid in the glassvessel'and the additional pressure required to lift the differential column above the top end of the tube 50. Thus, if for any reason. the gas pressure rises in the passage tlf.'ougl1 the tube to the patients mouth or nose to a point above the determined pressure under which the apparatus is ClEL-HgHCCl to work, that is to say, a pressure greater than the amount required to lift the said difi'erential column of liquid in the tubes -t9-50, this pressure will back up in the jar, or glass vessel, and act to force the liquid out through the tubes 4-9 50 and then into the open air, through a restricted aperture 50' at the top end of the tube 50, thus relieving the pressure within the jar and preventing the gas to the patient being anything above the determined pressure.

The use of the small inner tube 49 fixed in the constricted opening 49 at the bottom of the tube 49, prevents the seal forming liquid from being forced, or driven, in a great quantity from the vessel in case the pressure within the glass jar, or vessel, rises above the determined point.

To heat the gaseous or vaporous mixture, an electric heating unit 55 of any familiar construct on'is mounted in a suitable inverted tubular cup recess 56 (see Fig. 7

interior of the tubes turn, Warmsthe mixture forming gasesor vapors as they pass through it.

In order to drain the washing liquid from the jar 13, whenever or for whatever purpose required, a drain cock 58 is fixed to the bottom wall of thecasing 10. A passageway 59 is formed in saidbottom wall and connects said cock with the recess 26, heretofore described as being connected with the 14. and with the interior of the jar 13. r 1 r The graduated scale card or plate 48 is arranged in the vertical plane of the front of the sight feed tubes 1414* and said plate has its lateral upright edges bent to form arcuate wings or flanges 48 18 which embrace or inclose approximately two-thirds of the circumferential area of said tubes, so as to expose only the front sides of said tubes to view. Said plate 48 is fixed at'its top end to the metallic sections l4:"lt of said sight feed tubes Mir-14 and its arcuate wings or flanges 48 prevent buckling of the tube sections at the gasket'or washer 1& under the downward pressure exerted thereon when the head 11 is secured in place as before described.

Should it be desirous at any time to administer either of the gases forming the anesthetic mixture, separately, to. the patient, the handle 43 may be turned to close the valves 34-454- and the tube leading to the face mask or inhaler removed from the nippic 47 and connected to the nipple of either of shut-off valves 60-430 carried by the pressure reducing valve 3636, said valves 6060 of course communicating with the 36 36. The valves 60-60 are normally closed valves which may be readily opened to feed either gas to the patient, according to the needs arising from the conditions of the patient. As is apparent, this change may be made from a mixed gas to either separate gas and vice versa without disturbing the proportions of the mixed gases provided for by the adjustment of the valve stem 82.

The operating member 43 of the stem 42 not only affords a means whereby the valves 3l34 may be operated simultaneously but also affords acvery convenient handle by means of which the apparatus as a whole may be carried or moved about. The head 11 as will be apparent from the foregoing description, carries all of the valves used in the apparatus. This construction is'advantageous in that it increases the practicability of assembling or cleaning of the parts with out disturbing adjustments. In the use of the apparatus, it may become necessary. to renew or replace either one or both of the gas cylinders While the anesthetic or analgesic fiuid is being administered. The improved apparatus is of particular advantage at this time.

The natural and expect-ed thing to be done when a gas cylinder is to be replaced or renewed, would be to close the main shut oft valves operated by the handle 43. Under these conditions the mixture, with the determined portions of the two gases, would be administered to the patient under the gradually diminishing head due to the fact that the flow of gas from the two gas cylinders is stopped. This would be of no moment. however. as the time required in replacing the cylinder, or cylinders, would be but short. It may happen, however, that the attendant, by oversight or on account 0t attention to other matters, may fail to operate the handle 43 to close off the shut off valves from the gas cylinders. It is under such circumstances that my improved a paratus operates at a special advantage. Thus, su posing that with the said shut off valves still open one of the gas cylinders is disconnected. This leaves the reducing valve 36 associated with that gas cylinder open to the atmosphere. This will be of no moment, except for the escape of the gas in the line between the inlet of the reducing valve and the top of the liquid level in the associated sight feed tube to reduce the pressure in said line to atmospheric pressure. Any further escape of gas would be prevented by the liquid in the vessel 13 and in the sight feed tube. There would simply be a restoration of the balance of pressure between the liquid in the vessel and the liquid in the tube. and the liquid in the tube and in the vessel would form a seal to prevent the es cape of the mixture fr m the vessel.

Another advantage of the apparatus arises from the fact that the valves on the gas cylinders are apt to leak. no matter how t ghtly they are closed off. In the improved apparatus. if such leakage occurs. it will be immed ately detected, since it will be evidenced by the depression in the associated sight feed gage tube.

While in describing mv invention. I have referred to certain details of mechanical construction and arrangement of parts, I do not wish to be limited thereto except as may be pointed out in the a pended claims.

I. claim as my invention 1. In an apparatus of the kind described, a closed vessel having a transparent wall, tubes located in said vessel back of said transparent wall, said tubes being two-part tubes and one of said tube parts being transparent. means closing the top and bottom ends of said tubes and means connecting the interior of said tubes with the interior of said vessel so that a liquid contained in the vessel will normally stand at the same level in said vessel and in said tubes, openings in.

said tubes below the level of said liquid, means adapted to connect each of said tubes with a source of gas or vapor supply, each of said connecting means including a valve for adjusting the pressure of gas introduced by it, and means whereby the relative level of the liquid in said tubes below the level of the liquid in said vessel may be determined.

2. In an apparatus of the kind described, a closed vessel having a transparent wall, tubes located in said vessel back of said transparent wall, said tubes being two part tubes, and one of said tube parts being transparent, means closing the top and bottom ends of said tubes and means connecting the interior of said tubes with the interior of said vessel so that a liquid contained in the vessel will normally stand at the same level in said vessel and in said tubes, openings in said tubes below the level of said liquid, means adapted to connect each of said tubes with a source of gas or vapor and for adjusting the pressure of gas introduced by it, means whereby the relative level. of the liquid in said tubes below the level of the liquid in said vessel may be determined, and an index card associated with said tubes and visible through the transparent wall of said vessel, said index card being adapted for indicating the relative levels of the liquid in said tubes below the level of the liquid in said vessel.

3. In an apparatus of the kind described, in combination with a sight feed gage device including tubes having transparent parts, means inclosing said tubes and a body of liquid normally standing at the same level in said tubes and inclosing means, means connecting said tubes with a source of gas or vapor supply. said means including adjusting valves adapted to regulate the pressure of the gas or vapor admitted to the tubes and shut oft valves to control the admission of gas or vapor to said tubes, and a single controlling means adapted to simultaneously operate the several shut ofi' valves associated with said tubes.

4. In an apparatus of the kind described, in combination with a sight feed gage device including tubes having transparent parts, means inclosing said tubes and a body of liquid normally standing at the same level in said tubes and inclosing means, means connecting said tubes with a source of gas or vapor supply. said means including adjusting valves adapted to regulate the pres sure of the gas or vapor admitted into the tubes and shut off valves intermediate said adjusting valve and said source of gas or vapor supply. and a single controlling means adapted to simultaneously operate the several shut otf valves associated with the said tubes. I 5. In an apparatus of the kind descrlbed,

V 7 Copies of this patent may be obtained for in combinationwith a sight feed gage device including several tubes having transparent parts, means inclosing said tubes and a body of liquid normally at the same level in said tubes and in said inclosing means, means connecting said tubes with a source of gas or vapor supply, said connecting means including adjusting valves adapted to regulate the pressure of the gas or vapor admitted into the tubes, shut off valves to control the admission of gas or vapor to said tubes, and a reducing valve intermediate said shut oli' valve and said source of gas supply, and a single controlling means adapted to simultaneously operate the several shut oli' valves associated with said tubes. I I

6. In a device of the kind described in combination with a closed vessel having a transparent wall, parallel upright tubes closed top and bottom fixed in said vessel, said vessel and tubes containing a liquid, means connecting said tubes and vessel so that the liquid will normally stand at the same level in said vessel and in said tubes and each tube being provided with one or more gas discharge openings below the normal liquid level therein, one of said openings being of large diameter at its outer end and reduced in diameter at its inner intermediate end to eliminate capillary attraction.

7. In anapparatus of the kind described, a sight feed gage apparatus including a head, valves in said head and means for supporting said head, yokes adapted for the attachment of the necks of gas or vapor cylinders to said head, said yokes being substantially wider than the necks of said cylinders, and being fixed to said head in planes inclined to the vertical whereby the said cylinders may be adjusted at different angles when their necks are engaged in said yokes.

8'. In an apparatus of the kind described,

a tubular open top metal casing having a base and a bottom wall and being provided with a view opening, a tubular transparent vessel located within said casing, tubes ineluding transparent parts fixed in an upright position within said tubular vessel in line with said view opening, said tubes being provided with gasdelivery orifices, gaskets at the top and bottom of said vessel, a head closing the top of said casing, means for securing said head to'said "casing whereby '55 said tubes and said tubular transparent ves- 1 sel may be drawn up gas tight upon said 'ga'skets. the bottom wall of said casing being provided with a recess located below said transparent tube parts and the bottom gasket being provided with openings connecting said recess with said tubes and with the interior of said vessel.

9. In an apparatus of the kind described, a tubular open top metal casing having a bottom wall and being provided with a view opening, a tubular glass vessellocated within said casing, tubes having transparent parts located Within said tubular vessel in line with said view opening, said tubes being provided with gas delivery orifices, gaskets at the top and bottom of said vessel to close the top and bo-ttomends of said tubes and vessels, a head closing the top of said casing, mea-ns'for securing said head to said casing, said head being provided withbosses to form valve casings and inlet and outlet conduits, valve stems in said boss projecting above said head and a cap inclo'sing said head and provided with openings through which said valve stems project.

10. In a device of the kind described, in combination with a vessel having a transpare t wall and sight feed gage tubes contained therein, said vessel and tubes containing a liquid, means for introducing gas under pressure into said tubes for escape from said vessel above the level of said liquid, and means providing a liquid seal, closing said vessel and adapted to be broken when the pressure in saidve'ssel exceeds a certain amount.

11. In a device of the kind described, in combination with a vessel having a, transparent wall and sight feed gage tubes contained therein, said vessel and tubes contain ing a liquid, means for introducing gas under pressure into said tubes for escape from said vessel above the level of said liquid, means for fixing the maximum pressure to be attained in said vessel, consisting of a stand-pipe within said vessel'ope'n' at the top, and a tube depending into said stand-pipe and communicating with the atmosphere outside said vessel. said tube and said standpipe providing a liquid seal for said vessel and providing a head to determine the pressure that may be attained in 'saidvessel."

12. In a device of the kind described, in combination with a vessel "having a transparent wall, sight feed gage tubes contained therein and a liquid in said vessel and insaid sight feed gage tubes, and means contained Within said vessel for heating the liquid therein, whereby the gas or vapor escaping from said tubes may be heated on its way to dischargefrom said vessel.

In testimony, that I'clai-in the foregoing as my invention I'affix mysignature in the presence of two witnesses, this 27th day of April A. D. 1916'. K 3

MALCOLM F. EWEN. lVitness'es:

T. H. Amines, KARL N; DALL.

washington m, 

